Summary of the use of common commands for mysql columns-Mysql Tutorial-php.cn

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show all column propertyView the properties of all columns

Modify the column attributes of the table alter table modify

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Summary of the use of common commands for mysql columns

黄舟

Sep 26, 2017 am 11:16 AM

mysql use

The main content of this article is mysql column common commands:

View table column attributesdescribe table_name column_name
show all column property View the properties of all columns
Modify the column properties of the table alter table

modify

rename columnRename column

Add column (add index at the same time), delete column

Modify the default value of the column

View the attributes of the table column`describe table_name column_name`

Many times we need to view the column Details, for example:

describe springdemo.blog title;

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Summary of the use of common commands for mysql columns

show all column propertyView the properties of all columns

show fields from springdemo.blog;

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View all columns

Summary of the use of common commands for mysql columns

Modify the column attributes of the table alter table

modify

Modify the column attributes of the table alter table

modify

Summary of the use of common commands for mysql columns

##rename columnRename column

Modify the field name of the table alter table

change

Summary of the use of common commands for mysql columns

Note: The storage of data in the database has a great relationship with the data type, so do not change the data type casually

alter table springdemo.blog change title title_new nvarchar(60) comment 'Modified';

Add (add index at the same time), delete columns

alter table springdemo.tb_ms_audit_user_infoadd mal_report int default 0comment &#39;恶意举报的次数&#39;, add index(mal_report);

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删除字段 : alter  table  <表名>  drop  <列名>

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Modify the default value of the column

alter table tablename alter column drop default; #(若本身存在默认值，则先删除)alter table tablename alter column set default &#39;t5&#39;;# (若本身不存在则可以直接设定)

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Summary of the use of common commands for mysql columns

View the attributes of the table columndescribe table_name column_name

show all column propertyView the properties of all columns

Modify the column attributes of the table alter table

alter table tablename alter column drop default; #(若本身存在默认值，则先删除)alter table tablename alter column set default &#39;t5&#39;;# (若本身不存在则可以直接设定)Copy after loginBe sure to indicate the source when reprinting, and respect the work of others.

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View the attributes of the table column`describe table_name column_name`

alter table tablename alter column drop default; #(若本身存在默认值，则先删除)alter table tablename alter column set default 't5';# (若本身不存在则可以直接设定)
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Be sure to indicate the source when reprinting, and respect the work of others.